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    <title>Document</title>
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    <script>

        {
            var a = 1
            let b = 2
            const c = 3
            console.log(a, b, c)
        }
        console.log(a)
        /*--------------------------------------------*/
        const c = 20
        console.log(c)

        var obj = { //对象虽然有{} 但是它是数据 => 并不是作用域
            a: 1,
            b: 2,
            c: 3,
            // console.log(1);
            c: function () {
            }
        }



    </script>

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